In order to guarantee sufficient sample size, therefore, 300 patients must fulfil the study criteria (allowing for exclusion of 100 at time of operation). Recruitment of patients is not expected to be difficult because evidence to date is convincing of at least equivalent outcome and we believe that most patients would hope to be assigned to the lavage group in the hope of avoiding a stoma. From a surgeon's perspective, laparoscopic lavage is technically less challenging and time consuming than traditional treatment modalities.